Definitions
An "affect" is a transient feeling state. Typical negative affects are feelings of nervousness, tenseness, shame, anxiousness, irritability, anger, rage, and the like. "Moods" are longer lasting feeling states such as guilt, sadness, hopelessness, worthlessness, remorsefulness, misery, unhappiness and the like. "Character traits" are more permanent aspects of an individual's personality. Typical negative character traits are sensitivity, regretfulness, blameworthiness, stubbornness, resentfulness, bitterness, timidness, laziness and the like.
"Pregnane steroids" are aliphatic polycyclic hydrocarbons characterized by a four-ring steroidal structure with a methylation at the 10- and 13-positions and ethylation (including unsaturated groups) at the 17-position. The 19-nor compounds lack a methyl or other carbon-containing substituent on C-10 where C-19 would normally be found. A pregnene is a subset of pregnanes commonly understood to mean that the compound has at least one double bond.
A "chemoreceptor" is a receptor molecule displayed on the surface of a "chemosensory" neuroepithelial cell which binds in a stereospecific fashion to a particular ligand or ligands. This specific binding initiates a signal transduction which initiates an afferent nerve impulse. Chemoreceptors are found, inter alia, in taste buds, olfactory epithelium and vomeronasal tissue.
"Pregnene steroids", as the term is used herein, are aliphatic polycyclic hydrocarbons with a four-ring steroidal structure, at least one double bond in the A-ring, methylation at the 10-position and 13-position, ethylation (including unsaturated groups) at the 17-position and an oxo, hydroxyl or hydroxyl derivative such as an alkoxy, ester, benzoate, cypionate, sulfate or glucuronide, at the 3-position. The 19-nor compounds lack a methyl or other carbon-container substituent or C-10 where C-19 would normally be found. Derivatives which contain these structural characteristics are also referred to generically as pregnene steroids.
The following structure shows the four-ring steroidal structure common to pregnane and pregnene steroids. In describing the location of groups and substituents, the following numbering system will be employed: ##STR1##
"Sexually dimorphic" refers to a difference in the effect of, or response to, a pharmaceutical agent between males and females of the same species.
An "effective amount" of a drug is a range of quantity and/or concentration which brings about a desired physiological and/or psychological effect when administered to an individual in need of the drug. In the present case, a needy individual is one with a physiological or behavioral trait which is normally regulated by the hypothalamus and wherein it is desirable to affect the function of the hypothalamus or the trait. The effective amount of a given drug may vary depending upon the function to be affected, the desired effect, route of administration, and the like. For example, when the steroid in administered as a solution applied to the facial skin of a subject an effective concentration is from 1 microgram/ml to 100 .mu.g/ml, preferably 10 to 50 .mu.g/ml and most preferably 20 to 30 .mu.g/ml. When the steroid is introduced directly into the VNo an effective amount is about 1 picogram to about 1 nanogram, more preferably about 10 picograms to about 50 picograms. When the steroid is administered to the nasal passage, by ointment, cream or aerosol, or the like, an effective amount is about 100 pg to about 100 micrograms, preferably about 1 ng to about 10 micrograms. It follows that some drugs may be effective when administered by some routes, but not effective when administered by other routes.
The "hypothalamus" is the portion of the diencephalon comprising the ventral wall of the third ventricle below the hypothalamic sulcus and including structures forming the ventricle floor, including the optic chiasma, tuber cinereum, infundibulum, and mammillary bodies. The hypothalamus regulates the autonomic nervous system and controls several physiological and behavioral functions such as the so-called fight and flight responses, sexual motivation, water balance, sugar and fat metabolism, hunger, regulation of body temperature, endocrine secretions, and others. The hypothalamus is also the source of vasopressin which regulates blood pressure, and oxytocin which induces parturition and milk release. All hypothalamic functions are potentially modulatable by the vomeropherin therapy described herein.
A "ligand", as used herein, is a molecule which acts as a chemical signal by specifically binding to a receptor molecule displayed on the surface of a receptor cell, thereby initiating a signal transduction across the cell surface. Binding of ligands to chemosensory receptors can be measured. Chemosensory tissue, such as vomeronasal neuroepithelium or olfactory neuroepithelium, contains a multiplicity of neuroreceptors cells, each displaying at least one cell surface receptor. Many of the receptor molecules have identical ligand specificity. Therefore, when the tissue is exposed to a ligand for which it has specificity (for example a exposure of the VNO to a vomeropherin) a summated change in cell surface receptor potential can be measured.
As used herein, "lower alkyl" means a branched or unbranched saturated hydrocarbon chain of 1 to 4 carbons, such as, for example, methyl, ethyl, n-propyl, i-butyl and the like. "Alkoxy" as used herein is used in its conventional sense to mean the group --OR wherein R is alkyl as herein defined.
A "pheromone" is a substance that provides chemical means of communication between members of the same species through secretion and peripheral chemoreception. In mammals pheromones are usually detected by receptors in the vomeronasal organ of the nose. Commonly, pheromones effect development, reproduction and related behaviors. A "vomeropherin" is a more general term which includes pheromones and describes a substance from any source which functions as a chemosensory messenger, binds to a specific vomeronasal neuroepithelial receptor, and induces a physiological or behavioral effect. The physiologic effect of a "vomeropherin" is mediated through the vomeronasal organ.
A picogram (pg) is equal to 0.001 nanograms (ng). A ng is equal to 0.001 micrograms (.mu.g). A .mu.g is equal to 0.001 mg.
The invention is directed to a group of certain 19-nor pregnane steroids.
A subset of 19-norpregnanes within the group are believed to be novel. Syntheses are described herein for the following compounds as designated on the chart: Chart 1 includes 19-norpregnanes to which the invention is directed, but do not limit its scope. The synthesis diagrams that follow depict intermediate and substructure syntheses for the preparation of these 19-norpregnanes.